This invention relates to a method for manufacturing supports for a lithographic printing plate.
A variety of methods for manufacturing lithographic printing plate supports have been proposed. Some methods include electro-chemical or chemical treatment, in which methods it is essential to control electro-chemical or chemical reactions. For this purpose, the reaction time, liquid composition, solution temperature, and electrical condition are suitably controlled.
To accommodate a strong demand for increasing the productivity of processes for manufacturing supports for lithographic printing plate, it is necessary to decrease the treating time. For this purpose, increasing the temperature of the treating solution or increasing the longitudinal dimension of the tank in which the treating solution is contained have been attempted.
However, when the temperature of the treating solution is increased, scales form in the treating solution, with the result that the manufacturing equipment, such as the treating tank, becomes corroded. In the case where the length of the treating tank is increased, the cost of construction and the space required for the installation are significantly increased. That is, this method is disadvantageous in that the cost of equipment is high. In order to manufacture many various types of lithographic printing plates, but only a few of each type of plate, it is essential to make the time required for varying the treatment conditions as short as possible. However, in previously proposed methods, a lot of time and energy is required to increase or decrease the temperature of the treating solution.